The only way you are going to be able to do this is to restore to a recovery server. You can install SQL and EV onto the same server for recovery purposes.
You will need to do a Recovery of EV using Data Only Backups - check the Administrators guide for this chapter for a detailed step by step.
What you will need to restore to a recovery server.
1. SQL databases - EVDirectory Databases and Vault Store Databases.
2. Vault Store Partitions.
Once restored and EV is back up and running - you will need to export the Archive out to PST.